Combination adjustable belt-sanding machine



A. NORD Sept. 24, 1929.

COMBINATICN ADJUSTABLE BELT SANDING MACHINE Filed Aug. 16, 1926 2 Sheets-Sheet Sept. 24,

1929; A. NORD COMBINATION ADJUSTABLE BELT SANDING MACHINE Filed Aug. 16, 1926 2 Sheets-Sheet 2 Patented Sept. 24, 1929 UNITED STATES PATENT OFFICE AXEL NORD, F TACOMA, WASHINGTON, ASSIGNOR OF ONE-HALF T0 EDWIN PERSON,

. 0F TACOMA, WASHINGTON COMBINATION ADJUSTABLE BELT-SANDING MACHINE Application filed August 16, 1926. Serial No. 129,403.

This invention relates to machines adapted to smooth wooden surfaces with an abrasive, or sanded, belt and especially to that class of such machine as is adapted for use in sanding irregular surfaces, ordinarily known as scroll sanding machines.

The objects of this invention are, first, to provide a machine which can be used as an ordinary flat surface sander, or can be changed to a spindle sander adapted to smooth any of a great number of irregular shapes; second, to provide a device which will enable such change to be made quickly, with but small additional cost over a machine adapted for flat surface work only; third,

which can be applied to the present fiat sanding machine in use, thus enabling a furniture or other manufacturer to enlarge the utility of his present machine without demanding additional floor space, or great expense;

fourth, a provide various adjustable means whereby the position and attitude of the belt guide may be adjusted to bring the belt to the proper degree of tautness, to cause the belt to track correctly thereon, and to bring the guide into practical position whereby the article to be smoothed may be brought into contact therewith; and fifth, to. provide a cheap, durable and efficient machine, which is easy to set up and convenient to use.

I attain these and other objects by the devices, mechanisms, and arrangements illus trated in the accompanying drawings, in which- Fig. 1 is a front elevation of my complete machine as set up for use as an ordinary fiat surface or table sander; Fig. 2 is a similar view, on a larger scale, of the idler end thereof; Fig. 3 is an end view of a portion of the part shown in Fig. 2; Fig. 4 is a plan view thereof; Fig. 5 is a perspective view, on a larger scale, of the brace holder head of the revoluble top thereof; Figs. 6, 7, and 8 show the details of the means for adjustably mounting the several spindle sander guides on the braces by which they are mounted on the machine, whereby the guide may be adjusted relative to the brace to cause the belt to track correctly thereon, Fig. 6 beinga side elevation, Fig. 7 a longitudinal section, and Fig. 8 a

plan thereof; and Figs. 9, 10, 11, and 12 show various arrangements and shapes of the several spindle sander belt guides as mounted on the said brace-holder head of the machine. Similar numerals of reference refer to similar parts throughout the several views.

As shown in Fig. 1 the usual flat surface sander comprises a drive pulley 1, mounted on a suitable pedestal 2 and driven by a belt 3 from a motor 4, or by other means; an idler pulley 5, mounted on the opposite pedestal 6, in parallel arrangement and alinement with the pulley 1; a sand belt 7 having its abrasive surface outward, and running on the two said pulleys 1 and 5; a table 8, adapted to receive the article to be smoothed, and mounted on rollers 9 running, on the tracks 10, at right angles to the direction of motion of the said belt 7. The lower section of the belt 7 is pressed down by suitable manual means as it travels, on top of the article on the table 8.

In my improved machine I have changed the construction of the top of the second pedestal 6. This pedestal 6 is provided with the usual dovetail slot in its upper surface, and carries the plate 11, having a complementary dovetail lug 12 fitting in the said slot. The usual gear wheel 13, operated by the handle 14, engages suitable rack teeth out in the said lug 12 whereby the plate 11 may be moved to adjust the distance away from the drive pulley 1 of the machine.

The plate 11 carries a vertical screwthreaded pin 15, extending upward from a central point, and the revoluble head 16 is mounted thereon. This head 16 rests on the said plate 11 and is clamped down thereon by means of the hand wheel or nut 17 which is screwed on the said pin 15. The position of the head 16 on the plate 11 and about the central axis of the pin 15, may be adjusted in order to bringthe idler pulley 5 or other belt guide block into correct tracking position. This adjustment is obtained by means of a stop screw 18 passing horizontally through a short swingable arm 19 mounted on the fixed lug 20 on the side of the plate 11. The lug 19 may be swung down out of the path of the head16 to permit it to pass thereover when desired, or may be swung up to permit used, thus bringing the adjustable axis of the the said screw stop 18 to engage the side of the said head 16 and to hold it against displacement from such adjusted position by the force applied thereto from the tension of the sand belt 7.

The revoluble head 16 is provided on the upper side of one end with a horizontal boss 21 in which a horizontal shaft 22 is secured. This shaft 22 extends laterally from the said boss and head 16 and carries the idler pulley 5 which is preferably mounted on roller bearings on the said shaft 22; When the head 16 is swung into the position shown in Figs. 1l the idler pulley 5 is in line with the drive pulley 1 and the sand belt 7 may be passed over both of them and its tension adjusted by moving the plate 11 and the head 16 by the wheel 13, while the tracking of the said sand belt 7 may be adjusted by the stop screw 18 engaging the side of the head 16. This adjustment is often needed because the sand belt is made by gluing its ends together and therefore one edge may be slightly longer than the other, or it may stretch slightly more than the other under use. As soon as the adjustment is made the head 16 is clamped in place by screwing down the hand wheel 17 on the pin 15. In this position the work table 8 may be used in the ordinary manner.

A vertical boss 23, having a vertical hole 24 therein, is also formed adjacent to the horizontal boss 21, above described, and is adapted to adjustably hold a supplementary guide 4 block, similar to that shown in Fig. 9 and hereinafter described, whereby the two parts of the said sand belt 7 may be separated by a greater distance than the diameter of the idler pulley 5, if desired.

The other end of the revoluble head 16 is provided with a downward projecting lug 25 which is positioned substantially diametrically opposite to the said boss 21. This lug 25 (Fig. is provided with a plurality of horizontal holes 26 and vertical holes 27, therein. Each of these holes is provided with a key 28 adapted to engage and clamp the round brace bar, hereinafter described, under the action of suitable set screws 29.

In Figs. 6 to 12, I have shown several different forms of sand belt guide blocks and work rests or tables, adapted for use with different kinds of work and each adjustable in height and in distance from the drive pulley by manipulation of their respective brace bars in the said holes 26 or 27. These brace bars or arms are of dilferent forms and lengths, according to the particular shape and position of the belt guide block with which they are to be used, a few only being illustrated herein. In Fig. 9 two similar Z-shaped bars or arms 30 are shown, thus bringing the adjust-able axis of the blocks parallel with the holes in the lug 25 in which they are mounted; in Fig. 10 two right-angled arms 31 are being block or table at right-angles to that of the holes in which they are secured; in Fig. 11 a U-shaped bar 32 is illustrated; and in Fig. 12 a Z-shaped bar 30 and a right-angled bar 31 are shown. It is readily seen from the drawings that these bars or arms 30, 31 and 32 may each be adjusted axially and rotatably in the holes 26 or 27 in which they may be secured.

The connection between the several brace bars 30, 31 or 32 with the respective belt guide blocks is made adjustable around the axis of the bar and also at an angle relatively thereto, whereby the said belt guide block may be turned and tipped in order to cause the sand belt 7 to track properly thereon. This adjustment is illustrated in detail in Figs. 6, 7 and 8. The shank 33 of the particular brace bar is provided with a fixed collar 34 at the point where it enters the belt guide block. A slot 35 is made through the belt guide block, said slot having parallel sides but tapered edges (Figs. 6 and 7). .Vhen the belt guide blocks are made of wood, as is usual, I provide an entrance plate 36 through which the shank 33 passes and which rests against the said collar 34. The other end of the belt guide block is provided with a plate 37 secured to it, through which the end of the said shank 33 projects, and this plate is provided with parallel guide shoulders 38. A slide plate 39 is mounted between the guide shoulders 38 and is provided with. a boss 40 through which the said end of the shank 33 passes and in which it is secured by the key 41 and the set screw 42, whereby it is rotatably adjustable on the said shank 33. The fixed plate 37 and the slide plate 39 each have upward extending complementary lugs 43 through which the adjusting screw 44 passes. A keeper plate 45 may be secured over the slide plate 39 to hold it between the guide shoulders 38. Thus it will be seen that by turning the screw 44 the angle between the guide edge of the belt guide block and the axis of the shank 33 of the respective brace bar, may be adjusted as desired to cause the sand belt 7 to track.

The several guide blocks, above referred to, are preferably made of wood and may then be covered wit-h heavy canvas 54 (Fig. 7 which is thoroughly impregnated with glue, or made with any other suitable material. The belt guide block 16, shown in Figs. 6, 8 and 11, is provided with two rounded ends of different radii, each substantially a halfcircle, and joined by two flat surfaces of the, sides, all of which surfaces are adapted to act as a backing for the belt 7 as it passes thereover, and is adapted for smoothing small curves, scrolls, Queen Ann legs, etc; the two belt guide blocks 47 (Fig. 9) may be adjusted to occupy a great number of positions, in accordance with the convenience of the operator, and are especially adapted for use with a narrow belt for smoothing a very wide range of irregular shapes, generally pressing the work against the belt itself between the two said blocks 47 without any backing; the large belt guide block 48 10) is provided with three flat surfaces, a fourth slightly convex surface, and with four corners of different degrees of sharpness. A work rest or table 49 may be used in connection with this block 48 and it may be supported on a similar brace bar or arm 31 on which it may be tipped and adjusted to occupy any desired vertical angle, thus greatly adding to its utility. In this case, as in the block 46, the work is pressed against the sand belt as it passes over the fiat surface thereof, or over one of the curved or corner surfaces thereof. The belt guide block 50 (Fig. 12) is rotatably secured over the shank 33 of the brace arm 31 by a suit-able set screw 51, whereby it may occupy any one of four positions, though usually either of two opposite positions are used. The main portion of this block 50 is cylindrical, except that a narrow flattened surface is provided (on its lower side in the position shown in Fig. 12) and this main part is provided with a rectangular head 52. This block is arranged to smooth inside or concave curves, irregular flats and rounds. The work rest or table 53 spans any side of this block and acts as a guide for the work and can be adjusted for any desired angle.

It will be observed, from Fig. 1, that this machine, when used as a scroll sander, is very convenient in that it permits the workman perfect freedom of his feet whereby he may stand as close to his work as he desires; also that the several adjustments of the plate 11, head 16, the brace bars 3082, or the several belt guide blocks on said brace bars, are each independent of all the others and therefore any desired combination of adjustments can be quickly and easily made to bring the sand belt to the proper degree of tautness, to cause it to track properly, and to bring the Working portion to the desired height for the workman operating the machine. It is also apparent that the machine can be quickly changed for one or another class of work with the least waste of time and with the least investment of capital and of space.

Having therefore described my invention, what I claim is 1. In a belt sanding machine, the combination of a driven abrasive belt; a pedestal; a head revolubly mounted on said pedestal and carrying in two diametrically opposite positions thereon two belt engaging devices, either of which may be brought into line to engage and support said abrasive belt; a removable stop mounted on said pedestal and adapted to removably engage said revoluble head, whereby said head may be held from turning on said pedestal when one or the other of said belt engaging devices is in operation and whereby, when said stop is removed, said head may be turned to bring the other of said belt engaging devices into operative position.

2. A belt sanding machine as set forth in claim 1, wherein said removable stop is pivotally secured to said pedestal and is adapted to be moved into or out of position to engage said revoluble head to hold it or to permit it to turn on the pedestal.

3. A belt sanding machine as set forth in claim 1, together with an adjustable screw, passing through said removable stop and adapted to engage said revoluble head in adjusted position on said pedestal and to hold it from turning, whereby the belt is caused to track on the belt engaging device.

4. In a belt sanding machine, the combination of a pedestal with a head; a brace bar adjustably secured to said head and extending therefrom; a belt guide block loosely mounted on said brace bar; a plate secured to said block; a second plate secured to said brace bar and slidably mounted on said first plate; and adjustable means securing said plates together in adjusted position, whereby the block is secured to the brace bar and may be adjusted thereon.

5. A belt sanding machine as set forth in claim 4, wherein said second or sliding plate may be secured to said brace bar in revolubly adjustable position thereon, whereby different portions of the block may be brought under the belt engaged thereby.

AXEL NORD. 

